This invention relates to a roof ventilating device which is provided with a movable member that prevents wind driven snow or rain from entering the building.
Roof ventilators have been used to prevent dangerous heat build-up in the attics or upper floors of houses and other structures. One such roof ventilator is disclosed in U.S. Pat. No. 3,949,657 incorporated herein by reference. The roof ventilators disclosed in this patent provide a cover for an elongated opening cut along the ridge of a roof. The ventilating device covers the opening, and provides relatively narrow passages to vent heat from the interior of the structure. The passages are designed to be small enough so that entry of moisture is restricted. However, during storms, wind driven rain or snow could be forced into the roof opening through the passages if the wind is strong enough.
According to prior U.S. Pat. No. 5,921,863, incorporated herein by reference, a movable member has a pressure-responsive surface that responds to ambient winds speeds in excess of a predetermined level to move into a closed position closing the passages. Accordingly, entry of moisture into the structure is restricted. The movable member in this prior application is relatively inflexible. Furthermore, it has been learned that under certain atmospheric conditions, wind speed across the tip of the baffle and the top of the ventilating device can act to partially open the baffle even after it has been closed, thereby permitting moisture to enter the structure.
Other pressure-responsive moveable members are shown in U.S. Pat. No. 6,213,868 and U.S. patent application Ser. No. 09,727,720 by Applicant, both incorporated herein by reference.
One of the prior art roof ventilating devices is shown in FIGS. 1, 1A, 2, 3, 4, and 5. A roof ventilating device is shown generally by the numeral 10 and is installed on the ridge of a roof generally indicated by the numeral 12. Roof 12 includes a longitudinally extending ridge member 14 and transversely spaced rafters 16 which are covered by underlayment or sheathing generally indicated by the numeral 18. A portion of the sheathing or underlayment 18 adjacent the ridge board 14 is cut away to define a longitudinally extending vent opening 20 (FIG. 3). Shingles 22 are applied to the sheathing or underlayment 18 to complete the roof.
The ventilating device 10 includes a pair of vent parts 26 that are connected by a connecting portion 28. Each of the vent parts 26 extend along opposite sides of the ridge board 14 and provide a cap or cover extending over the vent openings 20. As more clearly described in the aforementioned U.S. Pat. No. 3,949,657, (the entirety of which is incorporated herein by reference) the vent parts 26 each include several courses or plies of a corrugated material manufactured of a waterproof or weatherproof construction, such as plastic box stock. Plies are generally indicated by the numeral 30. Accordingly, each of the plies 30 consists of generally parallel passages 32 provided by the box stock corrugations each of which provide a small diameter passage for communicating the vent openings 20 with ambient atmosphere. The ends of the passages 32 define an inner edge 34 of the vent part 26 which extends over the vent openings 20, and the outer ends of the passages 32 define an outer edge 36. The ventilating device 10 is installed on the roof 12 by appropriate fasteners (not shown), such as roofing nails driven through each of the vent parts 26 at appropriate intervals along the length of the ventilating device.
According to the invention, a flexible baffle generally indicated by the numeral 38 consists of a strip of cloth that extends along the outer edge 36 of each vent part 26. In the embodiment of FIGS. 1-5, the member 38 is constructed of TYPAR(copyright) Barn Construction Fabric, Part No. 3304T-002, available from Reemay, Inc., Old Hickory, Tenn. TYPAR(copyright) barn construction fabric consists of a one or more layers of spunbonded olefin sheets, as indicated at 39 of high-density polyethelene fibers, available from DuPont, Inc., as xe2x80x9cTyvek(copyright)xe2x80x9d, which has been coated with a polymer coating 41 available from Techmer Corp., Knoxville, Tenn., sold as PM-9098E4. The barn construction fabric was selected because of its durability, in that roofs are commonly replaced only after 20-25 years, and the TYPAR barn construction fabric has the necessary durability. Other fabrics, such as canvas, may be used, but may have be replaced at shorter intervals. The ventilating device 10 also includes an opposite upper surface 44, which is normally covered by shingles 46.
The baffle 38 includes an inner edge 40 (FIGS. 1 and 4) which is secured to the lower surface 42 (FIG. 3) of the ventilating device 10, which is applied directly to the roof 12. The ventilating device 10 also includes an opposite upper surface 44, which is normally covered by shingles 46. The movable member 38 is secured to the lower surface by a longitudinally extending sonic weld or impulse bond 48. The impulse bond 48 is formed in a conventional manner by bringing the welding head against the baffle 38 and compressing it against the vent part 26, heating the head, cooling the head, and then withdrawing the head. The head is heated for only a very brief time necessary to effect the weld, since the fabric or the cloth strip from which the baffle is made is relatively thin and appreciable heating would burn through the baffle. The outer end 50 (FIG. 4) of this movable member 38 is looped around and sealed to the flexible member by sonic welding or an impulse seal 52, which is formed in the same way as the impulse seal described above which attaches the baffle 38 to the corresponding vent part 26. Accordingly, an enclosed compartment is formed defining a compressible bubble 54. Of course, the movable member 38 may also be used without the bubble if desired, but as discussed above, the bubble 54 provides additional sealing when the movable member 38 is in the closed position.
As illustrated in FIG. 1, the member 38 may be divided into sections by kerfs 57 cut transversely across the strip, thereby permitting each individual section of the movable member to respond individually to ambient wind conditions. Of course, if a continuous and uninterrupted strip is provided, the strip opens and closes as a unit. In addition to kerfs 57, the movable member may also include slits 59 as shown in FIG. 1A to increase the flexibility of the member and provide a tighter fit against vent part 26 when closed. The slits may extend transversely across the bubble 54 to seal 52 or the slits may extend across only a portion of the bubble. These slits may also extend beyond seal 52, but this may result in tearing of the baffle under high wind conditions. The flexible member may contain both kerfs 47 and slits 59 or only one or the other.
When ambient wind conditions are low, the movable member 38 rests on the shingles 22, thereby opening the passages 32 to permit venting of air from the attic or upper story of the structure covered by the roof through the vent opening 20 and the passages 32. However, when ambient speeds increases to a predetermined wind speed, the movable member 38 responds to the wind, it being noted that the bubble 54 forms a lip which is caught by the wind, which forces the movable member to the closed position illustrated in FIG. 3. The width of the movable member 38 is such that the bubble 54 engages the corner 56 between the outer edge 36 and the upper surface 44 of the vent parts 26. Increasing wind speed thereafter compresses the bubble 54 against the corner 56, it being noted that the width of the movable member 38 is such that the bubble extends above the surface 54 a small distance. Because of the compression of the bubble 54 against the corner 56, a seal restraining entry of wind driven moisture and snow is provided, and the movable member 38 cannot be forced away from the edge 36 by aerodynamic conditions, as was the case in the prior art devices.
The present invention provides a movable member made out of cloth, which is relatively flexible and thus is able to close against the outer edge of the ventilating device more easily than the relatively stiff movable member disclosed in my prior application. Furthermore, the upper edge of the present invention terminates in a flexible cavity or xe2x80x9cbubblexe2x80x9d that extends longitudinally along the edge of the movable member. During storms, the movable member first moves into a position to close the vent openings, and the bubble is thereafter deformed against the upper edge of the ventilating device, thus providing a seal to assure that snow and moisture will not enter the vent passages. A lift spacer is provided on the movable member to provide a slight separation between the movable member and the roof while the movable member is an open position allowing air to vent through the vent openings. As wind speed increases, the lift spacer aids to allow air to pass beneath the movable member to facilitate the movable member moving into the closed position. The lift spacer also helps to prevent the movable member from becoming frozen to the roof in cold weather. The movable member acts as weather stripping that seals against the ventilating device in response to wind speed. Accordingly, the present invention of an elongated strip of cloth material having a bubble extending along one edge thereof may also be used as weather stripping around the edges of doors and windows. Furthermore, the deformable bubble may be used in other types of ventilating device according to other embodiments of the invention, in which a flexible bubble is mounted on relatively stiff baffles used in other types of ventilators.
These and other advantages of the present invention will become apparent from the following description, with reference to the accompanying drawings.